This invention relates to an electrochemical etching method for producing semiconductor diaphragms from a semiconductor wafer comprised of a first semiconductor layer of given conductivity type and a second semiconductor layer, formed on the first semiconductor layer, of different conductivity type than the first semiconductor layer.
Various electrochemical etching methods have been proposed. Although the conventional electrochemical etching methods are satisfactory for general applications, they may not provide sufficiently accurate diaphragm thickness control in specialized applications, particularly where the semiconductor diaphragms have a complex structure having an aperture(s).